Cylinder papermaking machine



Feb. 15, 1955 R F. HOLLIS CYLINDER PAPERMAKING MACHINE 3 Sheets-Sheet 1 Filed June 4, 1951 Abir .mint

Feb. 15, 1955 R. F. HoLLls CYLINDER PAPERMAKING MACHINE 3 sheets-sheet 2 Filed June 4, 1951 Nm .NIH

Feb- 15 1955 R. F. Ho| |s CYLINDER PAPERMAKING MACHINE Filed June 4, 1951 1117527 U2; ,13056.97 f HOLL /5 Evi/J 17 iff/.w EXT i CYLINDER PAPERMAKING MACHINE Robert F. Hollis, Alton, lll., assignor to Alton Box Board Company, Alton, Ill., a corporation of Delaware Application June 4, 1951, Serial No. 229,832

2 Claims. (Cl. 92-43) This is a continuation-impart of application Serial No. 713,203, filed November 30, 1946, now abandoned.

This invention relates to cylinder paper making machines, and especially to stock inlets or feed boxes for such machines. The problem of obtaining a uniform feed across the entire width of a paper making machine is particularly difficult in the case of a wide cylinder board machine. In a Fourdrinier machine the stock is applied directly to the forming wire, at a velocity corresponding to the velocity of the wire, in a broad thin stream. In a cylinder board machine, on the other hand, stock is fed to a vat circle in a relatively quiescent condition, since turbulence in the feed from the feed box interferes with uniform deposition of the web on the cylinder mold. In maintaining such a quiescent condition in the feed box difficulty has been experienced heretofore in that the stock tends to settle out, to clot, or lump, and in general to become non-uniformly distributed through the width of the feed box. The problem is recognized in U. S. Patent No. 1,964,291, but the device there disclosed has proved ineffective to solve the problem. In those vats which have been constructed in accordance with that patent, it has been necessary to provide an auxiliary inlet to achieve acceptable stock distribution and fluid tiow.

It has been discovered that uniform quiescent flow of stock from the feed box of a cylinder board machine can be accomplished without settling or segregating of the stock within the feed box by providing a vertical passageway of the feed box with a venturi throat through which all of the stock must pass, the cross-sectional area of the constriction of which throat bears a definite relation to the cross-sectional area of the vertical passageway.

' UnitedStates Patent O In accordance with the present invention, a venturi throat in a vertical passageway of the cylinder vat feed box has a cross-sectional area approximately one-sixth that of the cross-sectional area of the vertical passageway.

The venturi throat discharges into an open-topped chamber directly feeding the making board or weir discharge to the vat circle. The venturi throat may conveniently be provided by two opposed wall members in the feed box. In this manner the size and shape of the throat, within the prescribed limits, can be conveniently changed by vagying the shapes of the wall members, the feed box can be quickly opened up for cleaning, and standard cylinder vats can be easily equipped with a venturi throat of this invention.

IThe stock as it flows upwardly through the feed box and through the venturi throat has its velocity tremendously increased, thereby preventing any settling out or separation of ber bundles. In addition, the venturi throat, by providing a narrow gap in the feed flow along the entire width of the machine, acts as a stock spreader as well as a stock mixer to prevent development of uneven stock conditions at the making board or wer. It is not necessary that the stock be maintained under pressure after passage through the venturi throat since the pond maintained above the throat has a sufficient head to prevent spouting.

One of the objects of this invention is to provide a cylinder type paper making machine with a feed box from which the ow of stock is quiescent and uniform, and in which there is no segregation of stock.

Other and further objects of the invention will be apparent to those skilled in the -art from the following detailed description of the annexed sheets of drawings which, by way of a referred example only, illustrate one embodiment of e invention.

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On the drawings:

Figure 1 is a broken top plan view of a cylinder type paper making machine according to this invention and equipped with a venturi throat in the feed box end thereof and showing the throat-defining boards in a partially removed position.

Figure 2 is a transverse cross-sectional view, with parts in side elevation, taken along the line II-ll of Figure 1 and illustrating the cylinder in somewhat diagrammatic form.

Figure 3 is a front side elevational view of the cylinder machine taken along the line III-III of Figure 1.

Figure 4 is a fragmentary perspective view of one of the venturi throat-defining boards used in the feed box of this invention.

As shown on the drawings:

In Figures 1 to 3 inclusive the reference numeral 10 designates generally the stock vat of the cylinder machine of this invention. The vat 10 has a front side wall 11, a rear side 12, a rear end wall 13, and a front end wall 14. Arcuate partition walls 15 extending between the front and rear side walls 11 and 12 carry boards 15a and define a vat circle 16 in the vat. A cylinder mold 17 is rotatably mounted in the vat circle 16 and is supported on bearings 18 carried by the side walls 11 andv12. Partition walls are arranged in the vat to provide a trap or sump 19 at the bottom of the vat circle 16 which is drained by an outlet box 20 connected to a drain pipe 2l. Additional walls in the vat dene a sub-chamber 22 extending alongside of the sump 19 and fed by a pipe 23. An outlet slot 24 communicates with the sump 19 along the length thereof to join the chamber 22 with the sump for feeding diluting water, stock, or the like to 'the sump as desired.

The interior of the cylinder mold 17, discharges through an opening in the front side Wall 11 of the vat designated by the dotted line 25. This opening 25 is supplemented with a second opening shown by the dotted line 26; The two openings 25 and 26 control drainage of white water out of the interior of the cylinder mold, the water W- ing through the end of the mold. v

The front side wall 11, as shown in Figure 3, has a raised chamber-defining portion 11a communicating with the openings 25 and 26 and discharging to an outlet pipe 27 connected to the lower end of the chamber portion at the front end wall 14. As shown in Figure 2, the pipe 27 is underneath the partition wall 15 and is in a chamber 28 in the vat bounded by an upstanding end wall 29 in spaced parallel relation to the end wall 14 and an arcuate bridging top wall 30 joining the top of the wall 29 with another vertical wall' 31 secured on the upper end of the arcuate portion 15.

The raised portion of the front side wall 11 has a second drainage sump shown in Figure 3 communicating with a drain pipe 32. This drain pipe 32 is in a chamber 33 under the vat circle 15 between the rear end wall 13 and the walls defining the passageway 22. A gate or weir 34 suspended from a rod 35 carried by an adjustable lever 36 on top of the wall 11 is interposed between the opening 26 and the chamber-defining portion 11a of the front side wall 11 to control drainage of white water into the pipe 32. The arrangement is such that the pipe 27 drains most but not all of the white water out of the cylinder mold 17 at a rate insuliicient to maintain a white water level below the weir gate 34 so 'that the height of the gate determines the actual white water level in the cylinder rnold. The gate receives white water and foam thereover and discharges to the pipe 32.

The upper portion of the cylinder mold has communication with an exhaust pipe 37 connected to a titting 33 on the front side wall l1 having communication with the interior of the top of the mold. The pipe 37 is connected to a fan or suction device for drawing air from the mold.

The walls 14 and 29 shown in Figure 2 are in spaced opposed parallel relationship to define a vertical passageway 39 therebetween. This passageway is open at the bottom end thereof and is supplied with stock by means of a feed pipe or the like (not shown).

The wall 14 has a groove or recess 40 intermediate the top and bottom thereof and extending from the front to the rear side walls of the vat. This recess 40 has undercut or dovetailed top and bottom edges 40a. A similar groove or recess 41 is provided in the inner face of the wall 29 in opposed relation to the recess 40. This recess 41 has an undercut or dovetailed bottom edge 41a and an open top edge that registers with an undercut or dovetailed edge 41b in the wall member 30.

As shown in Figure 1, the front and rear side walls l1 and 12 have openings 42 registering with the space between the walls 14 and 29 and aligned with the recesses 40 and 41. These openings are closed by removable plzgez bolted or otherwise secured on the walls 11 an A metal plate 44 slidably tits in the recess or groove 40 and has beveled top and bottom edges tting the undercut edges 40a of this recess. The plate 44 is as long as the width of the machine to extend between the front and rear side plates 11 and 12. A wooden board 45 is carried by the front face of the plate 44, and this board has a curved contour so that it is thickest at its midportion.

A similar plate 46 lits in the recess or groove 41 on the wall 29 and has beveled edges for fitting in the undercut edges 41a and 41b. This plate 46 carries a wooden board 47 also of an arcuate contour to be thickest at its central portion. The two plates 44 and 46 with the boards 45 and 47 thereon are easily inserted in the recesses or grooves of the walls 14 and 29 through an opening 42 in the walls 11 and 12 as illustrated in Figure l. The plates when mounted on the walls carry the boards 45 and 47 in spaced opposed relationship to deline a venturi passageway 48 in the upper end of the vertical passageway 39. This passageway 48 converges to a relatively narrow throat extending across the full width of the passageway 39 and then diverges from this throat along a gradually widening path into an opentopped chamber 49 above the wall 30. As can be seen in Figure 2, the curvature of the board 47 is substantially a continuation of that of -the arcuate bottom-defining wall 30, so as to present a substantially smooth and continuous arcuate surface from the making board to the lower edge of the board 47. As can be seen from the same figure, the curvature of the board 45 is less than that of the board 47, and the board 45 extends above the upper edge of the board 47. Both of the boards 45 and 47 form parts of the surfaces of the walls on which they are mounted. The cross-sectional area of the throat of the venturi is approximately one-sixth that of the unconstricted part of the vertical passageway 39. This chamber 49 discharges into the upper end of the vat circle 16 over a making board 50. A gate or weir 51 is mounted behind the making board 50 and is raised and lowered by means of rods 52 in brackets 53 for varying the height of a pond maintained in the chamber 49.

In operation of the cylinder machine of this invention stock is fed into the bottom of the passageway 39 i from one or more feed pipes and flows upwardly through the passageway into the lower end of the venturi passageway. As the venturi passageway converges the pressure head of the stock is converted into a velocity head so that, by the time the stock reaches the narrow gap in the venturi throat, it is traveling at a very high velocity to equalize ow conditions across the entire width of the machine. Stock bundles or fibers cannot separate out at this high velocity. Such results are not accomplished if the area of the venturi throat is more than one-fourth or less than one-eighth of the area of the passageway 39. The rapidly owing stock leaving the venturi throat ows through the diverging passageway into the lower end of the chamber 49. This chamber 49 is maintained under atmospheric pressure since it has an open top.. However, it affords a suicient head to gevegt spouting of stock and undue agitation above the roa . The size or shape of the venturi throat, within the limits prescribed, can be varied at will by replacement of the-throatdefining boards 45 and 46. These boards and their supporting plates are easily removed so that the feed boxI can be opened up for cleaning. Stock entering the vat circle over the making board 50 is drained through the foraminous surface of the cylinder mold 17, the white water is removed as described hereinabove, and the stock fibers are deposited pn the foraminous surface in web form.

While the illustrative embodiment shown and described provides means for readily replacing the venturi throat of this invention it will be understood that the principles of this invention are applicable to various other constructions in which the venturi throat may be integral with or so mounted as to be more diicultly removable from the passageway ahead of the throat. Various other details of construction may be varied through a wide range without departing from the principles of this invention provided only that the ratio of the venturi throat opening to that of the passageway ahead of it be maintained at approximately l to 6.

Thus it can be seen that a feed box. for a cylinder paper making machine is provided which introduces the stock uniformly across the entire width of the machine, with no segregation of the stock in the feed box.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

l. A cylinder paper machine comprising a stock vat defining a vat circle and a feed box supplying stock to the vat circle over a making board, said feed box having a vertical stock supply passageway across the width of the vat, defined by two vertical walls, said feed box having a convexly. arcuate bottom extending between said making board and a contiguous wall of said passageway, the other wall defining said passageway extending above said bottom, a vertically arcuate wall member carried by the said contiguous wall and forming a part of the surface thereof, the curvature of said wall member being substantially a continuation of the curvature of the said bottom so as to provide a smooth arcuate surface between the making board and the lower edge of the wall member, said wall member extending across the width of the vat, a vertically arcuate opposing wall member carried by the other passageway-defining wall and extending across the width of the vat, said wall members forming a venturi throat, the ratio of the distance between said wall members at maximum constriction of the venturi throat to the distance between the walls below the throat being approximately one to six.

2. The cylinder paper making machine of claim l wherein the opposing wall member is of less curvature than and extends above the wall member carried by the contiguous wall.

References Cited in the tile of this patent UNITED STATES PATENTS 1,964,291 Kutter June 26, 1934 2,205,693 Milne June 25, 1940 2,339,730 Vedder Jan. 18. 1944 2,347,130 Seaborne Apr. 18, 1944 2,347,717 Staege Nov. 28, 1944 2,528,189 Temperley Oct. 3l, 1950 I 

